The invention relates to an implant needle for introducing an implant into a body of a patient and a method for production.
For inserting implants, e.g., sensors, into the skin up to an insertion depth of approximately 10 mm different types of implant cannula or needles are known, e.g., closed cannulas with a V-bevel, oval-shaped slotted cannulas with a V-bevel, and peel catheters, i.e., a cannula tube divided into two with a V-bevel which is then opened in the skin and removed in separate parts.
A flat sensor cannot be inserted into the skin with closed implant needles with a V-bevel, tubular. Oval-shaped slotted implant cannulas or needles are more expensive to manufacture than tubular slotted cannulas. They are predominantly used for 90° insertion angles. Peel catheters are also more expensive to manufacture and usually are only allowed to be inserted and removed by a doctor or nurse.
Document DE 10 2011 112 021 A1 discloses a needle or cannula provided with a tapered tip portion. Also, Document DE 102 24 101 A1 refers to cannula provided with a tapered tip portion. There are a first slant surface provided contiguous to an outer peripheral surface of the hollow needle main body and a pair of second slant surfaces contiguous to the first slant surface and symmetric with respect to an edge point and the axis of the hollow needle main body.
Document WO 99/53991 A1 refers to an implant retention trocar which includes a cannula for puncturing the skin of an animal and an obturator for delivering the implant beneath the skin of the animal. The implant retention trocar has a cannula distal tip design which causes a minimum of trauma and tearing of tissue during implant insertion. A spring element received within the cannula prevents an implant which is to be inserted into an animal from falling out of the cannula during the implant insertion process. The spring element includes a longitudinal leg which is folded with a zig-zag shaped bend. When the spring element is inserted into the cannula the zig-zag shaped bend of the shaped bend of the longitudinal leg retains the implant within the cannula.
Document US 2010/324579 discloses an instrument with a covered bore for subcutaneous implantation. An incising body defines a non-circular coaxial bore and includes a sharpened cutting edge that extends from a bottom distal end beyond the opening of the coaxial bore and an attachment point at a top distal end. A plunger is non-fixedly contained within the coaxial bore and slides longitudinally therein. A cover is pivotally attached at the attachment point and extends down to the bottom distal end and, when closed, the cover encloses the opening proximal to the cutting edge.
Document U.S. Pat. No. 3,064,651 relates to a hypodermic needle comprising an axial bore and being beveled at its outer end to provide a tissue penetrating tip and an obliquely disposed bore orifice extending rearwardly from said tip.
Document U.S. Pat. No. 3,448,740 refers to a noncoring hypodermic needle, comprising a heel portion and a tip portion terminating in a piercing point characterized in that at least one side wall portion is spirally curved from the piercing point to the heel portion and the heel portion is rotatably displaced approximately within the range of 260° to 280° and preferably about 270° from the piercing point in the same direction as the direction of spiral of said side wall portion.
Document WO 2005/044116 discloses a cutting device for a blunt needle or transcutaneous sensor for insertion through the derma of a patent, said blunt needle or transcutaneous sensor having a circumference at the distal end, said cutting device comprising a base part and a cutting member for making an incision in the derma, said base part having a track adapted for slideable engagement with the needle or transcutaneous sensor, wherein the cutting member has a cutting width, W, being less than half the length of the circumference of the blunt needle or transcutaneous sensor.
Document U.S. Pat. No. 4,490,139 refers to a subcutaneous implant needle formed as a hollow tube having its forward end cut on a plane at an acute angle to the central axis of the tube to form an elliptical opening, and an elliptical outer edge having a sharp forward portion. The forward extremity of the needle is dressed to form cutting edges intersecting at an obtuse angle and forming a central point. The dressed edges have a width preferably less than two-thirds the diameter of the tube, and the adjoining side portions of the elliptical outer edge are rendered unsharp and dulled, as by abrasion such as sandblasting or tumbling in abrasive media. The needle is dimpled at two locations closely adjacent the rear of the opening.